PhotosRepositoryTest.kt

@RunWith(JUnit4::class)
class PhotosRepositoryTest : MockWebServerBaseTest() {

    @get:Rule
    val testInstantTaskExecutorRule: TestRule = InstantTaskExecutorRule()

    private lateinit var photosRepository: PhotosRepository
    private lateinit var apiService: ApiService
    private val sol = anyInt()
    private val page = anyInt()

    override fun isMockServerEnabled() = true

    @Before
    fun start() {
        apiService = provideTestApiService()
        photosRepository = PhotosRepository(apiService)
    }

    @Test
    fun `given response ok when fetching results then return a list with elements`() {
        runBlocking {
            mockHttpResponse("json/photos_response_one_item.json", HttpURLConnection.HTTP_OK)
            val apiResponse = photosRepository.getPhotosFromApi(sol, page)

            assertNotNull(apiResponse)
            assertEquals(apiResponse.extractData?.size, 1)
        }
    }

    @Test
    fun `given response ok when fetching empty results then return an empty list`() {
        runBlocking {
            mockHttpResponse("json/photos_response_empty_list.json", HttpURLConnection.HTTP_OK)
            val apiResponse = photosRepository.getPhotosFromApi(sol, page)

            assertNotNull(apiResponse)
            assertEquals(apiResponse.extractData?.size, 0)
        }
    }

    @Test
    fun `given response failure when fetching results then return exception`() {
        runBlocking {
            mockHttpResponse(PhotosRepository.GENERAL_ERROR_CODE)
            val apiResponse = photosRepository.getPhotosFromApi(sol, page)

            assertNotNull(apiResponse)
            val expectedValue = Result.Error(Exception(SOMETHING_WRONG))
            assertEquals(expectedValue.exception.message, (apiResponse as Result.Error).exception.message)
        }
    }
}